The modern office utilizes space in many more effective ways than in the past. Although roll top desks are attractive and have interesting character, modern desks and workspaces are much more efficient. Cost of manufacturing workspaces is also more important as profit margins are squeezed and an improvements in worker efficiency is needed. Workspaces are now designed for individuals working alone and also for groups of workers who share part of a room. Cluster workspaces are being used where related tasks are being performed by several employees.
In order to increase the efficiency of space utilization at workspaces, cluster workspaces have been developed which use common partitions to divide an area into three, four or more individual work stations. Each station is personalized with specific, needed office equipment, such as word processors, computers, postal meters, and the like. In many cases, there is at least one person who experiences heat or cold to a greater or lesser extend than the other workers. Also, many times there are persons using the work stations who are allergic to smoke, dust, pollen and the like. These persons and all who work at work stations deserve and should have an appropriately clean and healthy environment in which to work.
U.S. Pat. No. 4,625,633 in the name of Martin, is a commonly owned patent which describes a ventilated core unit for service connections useful in work station arrays. Various prior art patents are disclosed the Martin Patent. The disclosure of all of those patents may be summarized by a statement in the Martin Patent that none of the prior art discloses the benefits of an independently controlled zone unit that is not attached to building HVAC equipment by air ducts.
Martin correctly identifies a modern trend in office furniture and layout arrangements in which small semi-private working cubicles are created a central core with multiple work stations and equipment emitting from that core. The Martin design has been very successful in providing a central core unit which accomplishes both ventilating and utility connections for peripheral work spaces.
The principal basis upon which the Martin invention is founded is the use of a central core unit for local ventilating, where the core unit also provides utility connections to peripheral work spaces around the core. A work space fan is mounted in a side wall of the cabinet. That fan is operable under user control to draw air from the work space into the plenum defined by the walls of the cabinet. The air is then discharged to the common area directly above the work space.
No system is perfect, however, and several drawbacks have been encountered in the use of the Martin system. Most of these drawbacks have been solved by the air circulation system described in commonly owned Mitchell et al U.S. Pat. No. 5,065,668. For the first time, it has been possible to obtain a class 100,000 rating for an office space, which is highly desirable for health reasons as well as for insurance ratings. The system includes the construction of a core having an inlet which draws an ambient air and an outlet which exhausts air such that the air flow combines with the side walls of a work station to enclose an individual using the work station in an envelope of processed air. Many newly installed work spaces have taken advantage of the Mitchell et al air circulation system to produce a plurality of work stations of optimum air quality and at the same time improve air quality in the entire room.
The Mitchell et al system requires the construction of a central core of at least sufficient size to process the air through the inlet and outlet. New construction of work stations is greatly improved by the Mitchell et al design, giving a better alignment of work space for a given quantity of available space. However, many work stations presently exist and would be suitable for continued use if the quality of the environment surrounding the work station could be improved. These existing work stations typically converge upon a central point rather than on a central core. These existing work stations may be visualized as being two or more walls which intersect each other to define work stations which are separated by a portion of each wall.
Another factor which has become significant in the design of office modules of the type described above is the need for controlling the noise in the environment directly adjacent to the worker. In the past it has been possible to `drown` out distracting noise by the use of a radio or other source of music. However, the distractions from that alternative are also a problem for those interested in maximizing efficiency while also providing the most appropriate work station. Systems which provide fresh air often times provide air at a velocity which blows papers around or otherwise distracts those working at the table or desk. Sometimes the noise is just too great and the worker seeks peace by turning off the fan, thereby giving up the advantage of fresh or purified air.
At the present time there is no effective answer to the needs of those who would seek to provide purified, fresh air in an already existing work station environment. One of the major problems is the need to filter air, such as by using the HEPA filter used in the above referenced Mitchell et al system, without creating such a large unit that it dominates the work station. Mitchell et al accomplishes effective space utilization by using the central core about which the work station is built, which as mentioned is effective for new construction.
To provide a motor capable of 150 to 300 cubic feet per minute (CFM) of air flow as does Mitchell et al is not practical for existing systems for two reasons. First, the size of the motor would be excessive. Second, the noise generated by the motor and fan ducts would also be excessive. Accordingly it would be of great advantage in the art if a design could be provided which is capable of moving a desired quantity of air though a HEPA filter at the appropriate CFM rate of flow while maintaining minimal noise levels, operating cost efficiencies, and cabinet or enclosure size parameters.
It is therefore an object of this invention to provide a device which will significantly improve the environment of these work stations without requiring major modification or replacement of existing walls.
Another object of the present invention is to provide an air circulation system which is effective in removing particulates from the air proximate the work station.
Still another object of this invention is to provide air circulation that is effectively sized and yet is quiet and does not disturb the worker or other persons in the immediate environment.
Other objects will appear hereinafter.